205 Heater fan - how to re-lube?

Posted this on the "tech" forum, is this a more appropriate place for it?
Anyhoo.....

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Hi,

My heater blower (fan) hasn't worked since i got my s2 GTI 6 months ago, and after the last scary steam-up situation, i decide its time to fix!

Unscrewed the fan and connected it to the battery, worked fine, a bit noisy (dry scraping sounding) though.

I used a bit of switch cleaner on the connections and it has quietened the noise down. The problem i'm having is that the fan wont start spinning unless i give it a little encouragement by hand...
I pulled lots of dead leaves and crap out of the motor and i reckon its probably just a bit dry.

I'd like to try and re-lube the bearings (if its possible) to see if this would reduce the friction enough to allow the fan to get going by itself. Is this something that a bit of WD40 would do or do i need to dismantle (and if so how) the motor and grease bearings etc.

If i'm on the wrong track with this thinking, i'd appreciate any ideas.

The speed control unit on the dash works fine once the fan is spinning so i think the control unit is probably ok, and i've also fitted a new battery so it should be getting enough voltage (i think i'll check the output voltage on the connector block to see what it is giving out).

Hi Dave. I don't have specific experience with the 205 fan motors, but I've revamped a few now for different cars, the last being two for a '68 E-Type Jag, so you can imagine how bad they were. (I've also done the R12 fan, the washer pump for the Mi, and a Davies Craig cooling fan for a friend). Anyway, they usually have sleeve bearings which are like a bronze porous bush that is 'self lubricating'. What you do is pull the motor apart and usually it's the shaft that's corroded, causing binding - obviously the bronze doesn't corrode easily. If this IS the case, use 1200 grit carborundum and WD40 and polish up the shaft where the bush runs. While you're doing this, soak the bushes in engine oil. They are meant to hold some oil in the pores in the metal and are actually heated in oil when made, I believe. I've seen people squeeze them between their fingers to force oil in, but I don't think this works. Not sure.

Then clean out the inside bore of the bush with a cotton cloth and reassemble, checking how free the shaft runs. Should be fine. Don't use WD40 as it will only last about a month, if it works at all. You don't want to burn out the motor, as this'll cost you much more.

Thanks for the reply, the shaft is indeed pretty coroded... So i'm gonna have a go at it as you suggested, my only fear is that the actual plastic "fan" cylinder will break when i'm trying to get it off the shaft, its pretty fragile....

Thanks for the reply, the shaft is indeed pretty coroded... So i'm gonna have a go at it as you suggested, my only fear is that the actual plastic "fan" cylinder will break when i'm trying to get it off the shaft, its pretty fragile....

I'll have to be careful!

Thanks again.
Dave

Dave

How interesting that you are working with this as today I removed and cleaned out the blower motor on my daughters 205 SI (series 2/3).. I see from your post that you have removed the motor.

The reason I removed the motor was that the fan was making a noise as if something was stuck inside the housing. Like you, the problem turned out to be leaves and accumulated crap in the centre of the blower. However, as I had the motor out I elected to open it up to be sure there was nothing else stuck inside. Just as well as it turns out because there were more bits of crap under the fan and inside the square lower tube section that postions the motor against the fiirewall. My findings / experience:

1. The three screws that hold the motor in place were all corroded and the self retaining 'speed nuts' all had corroded as well. This turned out to be the most time consuming part of the exercise as for each nut I ended up cutting a small piece of mild steel strip, drilled a hole for the self tapping screw, then soldered the piece of steel to the back of the retaining nut. It would have been nicer to silver solder the parts together, but as I no longer have that capacity, soldered was the way to go. It was important to repair the existing nuts this way because of the way the nuts slip over the edge of the plastic housing. Otherwise there was nothing left for the retaining screws to hold.

2. There was additional muck and bits and pieces at the base of the motor and a few hairs wrapped around the motor shaft near the bearing.

3. The blower fan is retained on the shaft by a special locking washer that has three small metal spikes folded at 90 degrees to the washer. These spikes are pushed into the blower fan One spike broke off, but I was able to re-use the washer to secure the fan later. [ So it is imporant to take care when removing the bloiwer fan because you will need the washer.] To remove the lock washer, prise it up with a scredriver until you have enough room to grip the end of the shaft with some pliers and rotate the fan. Complete removal of the fan requires a flat punch on the end of the shaft

4. The motor shaft was corroded above the fan and that was easily cleaned with sand paper.

5. The motor cannot be taken apart unless you want to go to a lot of trouble in opening up rivetted components. However you should not have to take the motor apart. The bearings are scintillated bronze and each is held with a retaining spring. I found the brushes and commutator to be in good condition as well as the lubrication on the shaft. If necessary you would be able to change the brushes. I removed all dirt and rubbish, cleaned off a little surface corrosion and gave the bearings a little oil (light grade Singer sewing machine oil) and reassembled.

6. (An addition)... as it turned out, cleaning the fan and removing the internal rubbish had the effect of increasing the end play on the motor shaft which resulted in the blower motor occasionally squealing. The remedy: remove the motor (easy this time) and adjust the end float. That also was easy as the end float is controlled by a lock washer pushed on to the shaft and accessible by removing the rubber end plug on the motor housing. A couple of taps using a small tube spanner immediately corrected the end float.

Thanks for the PM, much appreciated, think i should be cool with the very detailed and descriptive post above - I'm a bit nervous about rumagging inside the ducting to get the leaves out though, i'm a brit and you guys have mighty big spiders out here - and i've heard a few horror stories about the little critters getting into the vents!

Thanks for the PM, much appreciated, think i should be cool with the very detailed and descriptive post above - I'm a bit nervous about rumagging inside the ducting to get the leaves out though, i'm a brit and you guys have mighty big spiders out here - and i've heard a few horror stories about the little critters getting into the vents!

Thanks again for yor help.

Cheers
Dave

Dave

No need to be nervous about rummaging inside the ducting --- it's not a place for any spider. About the only types that I know to frequent the coachwork of a car are huntsmen -- the big hairy ones, presumably because they can get a good supply of insects for food. The other type that you would (or should feel at home with) is the redback (like the UK black widow but with a red spot on its backside) and they like the underside of tin cans, picnic tables and so on. I've not heard of one making its home in a car, then again if the car was stationary for long enough, I suppose you could find them there.

Then again you could use compressed air to save your fingers..

Actually removing the fan and /or the speed controller and servicing them is very easy.